Two men - including one from Chesterfield - are due to appear before a court in London charged with terrorism offences.
Andi Sami Star, 31, of Sheffield Road, Chesterfield, and Farhad Salah, 22, of Brunswick Road, Sheffield, have been charged with engaging in the preparation of an act of terrorism, it emerged late last night.
Both men will appear before Westminster Magistrates' Court via video link today.
The suspects were among four men arrested in Derbyshire and Sheffield on Tuesday last week following an investigation led by Counter Terrorism Policing North East (CTPNE) and supported by Derbyshire and South Yorkshire police.
A third man, a 36-year-old from Burngreave in Sheffield, remains in custody.
A 41-year-old Sheffield man was released without charge on Saturday.
• A CTPNE spokesman said: "Derbyshire Constabulary and South Yorkshire Police continue to work closely with their partners and communities to reassure local people and protect the public.
"If you see or hear something which could be terrorist related, act on your instincts and call the police in confidence on 0800 789 321.
"In an emergency, dial 999."